A thermal management system removes unwanted heat from one (or more) warm-temperature heat source(s), and rejects, i.e. directs, the heat to one (or more) heat sink(s). Thermal management systems are critical components of larger systems that, for example, generate large amounts of unwanted heat and/or generate unwanted heat with a high heat flux (heat flux is defined as heat flow per unit of area, which can be expressed in the units of Watts/(cm2).
There are many specific examples of critically needed thermal management systems for use on various navy ships, particularly warships. Future warships will include advancements in power electronics that enable technologies such as the integrated power system (IPS), electromagnetic weapons (EMW), high power radar, and others. The solid state power conversion inherent in the new technologies produces heat loads in excess of those in today's shipboard electrical systems. As these technologies become fully implemented, the population of solid state power conversion devices will increase, and, because warships typically have limited space, the power density of the devices and the heat fluxes of the generated heat will experience a comparable increase. The heat fluxes of the generated heat in the devices will eventually surpass 1,000 W/cm2, but existing technologies are limited to cooling heat fluxes of only approximately 100 W/cm2.
Heat acceptors (for example, heat acceptors that use jet impingement or droplet impingement) are being developed to remove high heat fluxes (up to 1,100 W/cm2 or more), but the thermal management systems that contain the heat acceptors waste the removed heat by rejecting the heat directly to heat sink(s). Cooling or heating is often needed in close proximity to the sources of high heat flux. Space cooling of compartments that will contain high-heat-flux power electronics will be required. Thermal management systems will remove heat from the high-heat-flux power electronics and reject the removed heat to a fresh water cooling loop; however, thermal management systems for many other components in the compartments will reject heat to the compartment air. Therefore, cooling will be needed to remove heat from the compartment air and prevent excessively hot air temperatures in the compartments.
An absorption heat pump accepts heat from one (or more) warm temperature heat sources(s) and generates either refrigeration or heating. When an absorption heat pump generates refrigeration, it absorbs heat from a cooling load and rejects heat to a heat sink. When an absorption heat pump generates heating, it absorbs heat from a cool temperature heat source and rejects heat to a heating load. Many alternative systems are capable of using heat from a warm temperature heat source to produce refrigeration or heating. However, for a given amount of heat input from warm temperature heat source(s), absorption heat pumps can produce more refrigeration or heating than the alternative systems if the difference between the temperature(s) of the warm-temperature heat source(s) of the heat sink(s) or the cool-temperature heat source(s) is small.
Therefore, a need exists for a thermal management system that uses one or more absorption heat pump(s) to provide either refrigeration or heating.